[Targets] Implement getConstraintRegister for ARM and AArch64
Summary:
The getConstraintRegister method is used by semantic checking of
inline assembly statements in order to diagnose conflicts between
clobber list and input/output lists. Currently ARM and AArch64 don't
override getConstraintRegister, so conflicts between registers
assigned to variables in asm labels and clobber lists are not
diagnosed. Such conflicts can cause assertion failures in the back end
and even miscompilations.
This patch implements getConstraintRegister for ARM and AArch64
targets. Since these targets don't have single-register constraints,
the implementation is trivial and just returns the register specified
in an asm label (if any).
Reviewers: eli.friedman, javed.absar, thopre
Reviewed By: thopre
Subscribers: rengolin, eraman, rogfer01, myatsina, kristof.beyls, cfe-commits, chrib
Differential Revision: https://reviews.llvm.org/D45965
llvm-svn: 331164
diff --git a/clang/lib/Basic/Targets/AArch64.h b/clang/lib/Basic/Targets/AArch64.h
index 0634565..f493ff2 100644
--- a/clang/lib/Basic/Targets/AArch64.h
+++ b/clang/lib/Basic/Targets/AArch64.h
@@ -82,6 +82,11 @@
std::string &SuggestedModifier) const override;
const char *getClobbers() const override;
+ StringRef getConstraintRegister(StringRef Constraint,
+ StringRef Expression) const override {
+ return Expression;
+ }
+
int getEHDataRegisterNumber(unsigned RegNo) const override;
};
diff --git a/clang/lib/Basic/Targets/ARM.h b/clang/lib/Basic/Targets/ARM.h
index 4e8e514..9c72c33 100644
--- a/clang/lib/Basic/Targets/ARM.h
+++ b/clang/lib/Basic/Targets/ARM.h
@@ -156,6 +156,11 @@
std::string &SuggestedModifier) const override;
const char *getClobbers() const override;
+ StringRef getConstraintRegister(StringRef Constraint,
+ StringRef Expression) const override {
+ return Expression;
+ }
+
CallingConvCheckResult checkCallingConvention(CallingConv CC) const override;
int getEHDataRegisterNumber(unsigned RegNo) const override;